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'Tracking the effects of land use and management on vegetation condition'. Staff seminar given on 6 March 2013 to NSW Office of Environment and Heritage, Goulburn Street, Sydney.
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Tracking the effects of land use and management on vegetation condition
Richard Thackway
Presentation to NSW OEH6 March 2013
Outline
• Concepts and definitions• Background to VAST framework• Why VAST-2 was developed• VAST-2 methodology • Case studies• Lessons • Where to here?• More information
Goals of land managers
Changes in ecological function
Values and decisions matrix:• Social• Economic• Environmental
Intensification
Degradation?
Goals of land managers
Changes in ecological function
Values and decisions matrix:• Social• Economic• Environmental
Extensification
Restoration
Regulation of hydrological regime Generation of food and fibre Regulation of climate / microclimate Generation of raw materials Recycling of organic matter Creating and regulating habitats Controlling reproduction and dispersal
Changing ecological function to derive multiple benefits (ecosystem services)
Drivers for information on changes in vegetation condition
• NRM policy and program design e.g.
– Implementing guidelines for conservation and management of threatened species
EPBC ACT
– Reporting on the performance of investment e.g. changing LMP to improve
landscape connectivity
– Assessing land acquisitions for the National Reserve System
• Resource condition of native vegetation e.g.
– A measure of sustainable use and management (public & private)
• Monitoring and reporting and improvement e.g.
– National, state & regional reporting e.g. SoE & SOFR
– Reporting 5 yearly outcomes Regional Forest Agreements
What is condition and transformation?
• Changes to a plant community caused by landuse
/management
– Structure
– Composition
– Regenerative capacity
• Transformation = changes to vegetation condition over time
• Condition and transformation are relative to a reference state
Vegetation condition
Vegetation Assets States and Transitions (VAST) framework
VIVIVIIIIII0
Native vegetationcover
Non-native vegetationcover
Increasing vegetation modification from unmodified state
Transitions = trend
Vegetation thresholds
Reference for each veg type (NVIS)
VAST - A framework for compiling & reporting vegetation condition
Condition states
Unmodified Naturally bare
Modified Transformed Replaced -Adventive
Replaced - managed
Replaced - removed
Thackway & Lesslie (2008) Environmental Management, 42, 572-90
Diagnostic attributes of VAST states:• Vegetation structure• Species composition• Regenerative capacity
NVIS
Why VAST-2 was developed?
• To implement the ‘T’ (Transition) of the VAST framework– i.e. track changes in vegetation condition over time
• To provide a practical tool for understanding and reporting the status of native vegetation over time
• To propose a standardised national system for compiling data on cause & effect of management on native plant communities
VAST – a snapshot
Thackway & Lesslie (2008) Environmental Management, 42, 572-90
NB: Input dataset biophysical naturalness reclassified using VAST framework
Models of ecosystem change
Source: Adamson and Fox (1982).
Time
Chan
ge in
veg
etati
on in
dica
tor
Settlement
10000
Reference
Occupation
Relaxation
Anthropogenic change
Net impact
Time
1800 1850 1900 1950 2000
Based on Hamilton, Brown & Nolan 2008. FWPA PRO7.1050. pg 18Land use impacts on biodiversity and Life Cycle Analysis
Reference
Models of ecosystem changeCh
ange
in v
eget
ation
indi
cato
r
Aim of VAST-2
Indigenous land management
First explorers
Grazing
Deg
ree
of
mod
ifica
tion
Logging
Cropping
Site 1
Site 2
Site 3
Time
Reference state
Long term rainfall
Long term disturbance e.g. wildfire, cyclones
Revegetation
VAST classes
VAST-2 System
Condition components
(3)
Attribute groups
(10)Description of loss or gain relative to pre settlement indicator reference state
(22)
Regenerative
capacity
Fire regime Area /size of fire foot prints
Number of fire starts
Soil hydrology Soil surface water availability
Ground water availability
Soil physical state
Depth of the A horizon
Soil structure
Soil nutrient state
Nutrient stress – rundown (deficiency) relative to soil fertility
Nutrient stress – excess (toxicity) relative to soil fertility
Soil biological state
Recyclers responsible for maintaining soil porosity and nutrient recycling
Surface organic matter, soil crusts
Reproductive potential
Reproductive potential of overstorey structuring species
Reproductive potential of understorey structuring species
Vegetation structure
Overstorey structure
Overstorey top height (mean) of the plant community
Overstorey foliage projective cover (mean) of the plant community
Overstorey structural diversity (i.e. a diversity of age classes) of the stand
Understorey structure
Understorey top height (mean) of the plant community
Understorey ground cover (mean) of the plant community
Understorey structural diversity (i.e. a diversity of age classes) of the plant
Species Compositi
on
Overstorey composition
Densities of overstorey species functional groups
Relative number of overstorey species (richness) of indigenous to exotic species
Understorey composition
Densities of understorey species functional groups
Relative number of understorey species (richness) of indigenous to exotic species
Step 7Add the indices for the three components to generate total transformation
index for the ‘transformation site’ for each year of the historical record . Validate using Expert Knowledge
Step 1aUse a checklist of 22 indicators to compile
changes in LU & LMP* and plant community responses over time
Transformation site
Step 1cEvaluate impacts on the plant community
over time
Step 1bEvaluate the influence of climate, soil and
landform on the historical record
Step 2Document responses of 22
indicators over time
Step 4Document the reference states for 22 indicators
Step 3aLiterature review to determine the
baseline conditions for 22 indicators
Step 3cCompile indicator data for 22 indicators for reference site
Step 3bEvaluate the influence of climate, soil and landform for the reference site
Reference state/sites
Step 5Score all 22 indicators for ‘transformation site’ relative to the
‘reference site’. 0 = major change; 1 = no change
Step 6Derive weighted indices for the three components for the ‘transformation
site’ i.e. regenerative capacity (58%), vegetation structure (27%) and species composition (18%) by adding predefined indicators
General process for tracking changes VAST-2 system
* LU Land useLMP Land management practices
Method: VAST-2
Species
composition
LU = Land Use, LMP = Land Management Practices
Indicators of VAST diagnostic attributes
LU & LMPYear
Time
Vegetation structure Regenerative
capacity
Year Source Year and reliability
LU & LMP Source: LU & LMP
Reliability of LMP
sources and spatial
accuracy
Effects of use and land management practices on
structure, composition and function
SourceEffects
Reliability of effects
and spatial accuracy
1800
1840
2013
Pre-contact
First contact
Current year
LU = Land Use, LMP = Land Management Practices
Method: VAST-2
Scoring impacts of land management practices
• All management practices are directed at e.g.– Vegetation/plants, soil, landform, water, animal, air
• Five objectives summarize all vegetation management– Establish and rehabilitate– Improve and maintain growth and condition– Harvest plant products and remove waste and weeds – Monitor health, vitality and condition– No activity or interventions
• Combinations of 5 objectives are common (space & time)• Impacts of LMP are scored for each VAST-2 indicator relative
to indicator’s reference state for each year
1
3
10
22
Dia
gnos
ticatt
ribut
es
VegetationTransformation
score
Attrib
ute
grou
ps
VegetationStructure
(27%)
Overstorey
(3)
Understorey
(3)
SpeciesComposition
(18%)
(2)
UnderstoreyOverstorey
(2)
RegenerativeCapacity
(55%)
Fire
(2)
Reprodpotent
(2)
Soil
Hydrology
(2)
Biology
(2)
Nutrients
(2)
Structure
(2) Indicators
VAST-2 hierarchy
Certainty level standards used to compile historic record
Certainty level standards
Spatial precision(Scale)
Temporal precision(Year of observation)
Attribute accuracy(Land use, land
management practices, effects on condition)
HIGH "Definite”
Reliable direct quantitative data.
Code: 1
Reliable direct quantitative data.
Code: 4
Reliable direct quantitative data.
Code: 7
MEDIUM "Probable
"
Direct (with qualifications) or strong
indirect data.
Code: 2
Direct (with qualifications) or strong
indirect data.
Code: 5
Direct (with qualifications) or strong
indirect data.
Code: 8
LOW "Possible"
Limited qualitative and possibly contradictory
observations. More data needed.
Code: 3
Limited qualitative and possibly contradictory
observations. More data needed.
Code: 6
Limited qualitative and possibly contradictory
observations. More data needed.
Code: 9
Reliability levels of attribute information
Quadrat or pixel
Land unit
Land system
Sub-bioregion
Bioregion
Certainty levels
Coarse
Fine
Low
Low
Medium
Medium
High
Sources of information
Granularity of information
Case studies VAST-2
Cumberland State Forest 1941-2012
Red boundary shows main compartments that were cleared as per the 1943 aerial photograph. This area was fully planted out around 1944 as part of the arboretum. Except for regrowth forests: i.e. compartments 8a, 9a, 9b and 10b
1941
1943
1951
1978
1982
1984
1999
2011
2012
T1
T2
On-ground field survey 2012
Transect 1Cumberland SF, ex-comp 8b, 9a, 9b.Regrowth forest
Transect 2Cumberland SF, ex-comp 3a, 7a, 7b, 7c.Repurposed arboretum
On-ground field survey 2012
VAST Unmodified
NSW, SB Bioregion, Cumberland SF, ex-comp 3a, 7a, 7b, 7cReference pre-European: Sydney Blue Gum High Forest
Commenced managing area for recreation. Weed control. Arboretum abandoned
Cleared & sown to improved pasture for grazing & orchard
Commenced grazing native pastures
Indigenous people manage the area
Area gazetted as State Forest, commenced planting arboretum
Area logged for building houses and fences
Commenced managing area as a future production forest. Weed control
Explorers traverse the area and site selected
Ceased grazing. Area purchased as a future working forest
VAST Unmodified
Commenced managing area primarily for recreation
Ceased grazing. Purchased & declared as a State forest
Site fenced. Commenced continuous stocking with cattle
Commenced grazing cattle
Indigenous people manage the area
Cleared and commenced regrowing forest as a future forest production
Tree cover thinned for cattle grazing
Initiated 1st hazard reduction burn
Trees logged for housing, fences & fire wood
NSW, SB Bioregion, Cumberland SF, ex-comp 8b, 9a, 9b Reference pre-European: Sydney Blue Gum High Forest
• Network of collaborators• Ecologists, academics, land managers, environmental historians,
educators
• Inputs• Reference state • Land use• Land management practices• Natural events e.g. droughts, fires, floods, cyclones, average rainfall
1900-2012 etc• Observed interactions e.g. rabbits, sheep and drought• Observations and quantitative measures of effects
• Include written, oral, artistic, photographic and remote sensing
Resources needed to compile and analyse an historical record for each site
VAST-2 Lessons
• Useful tool for:• engaging a wide range of collaborators and stakeholders incl:
• ecologists, academics, land managers, environmental historians, educators because it builds on VAST, which is widely accepted and used
• synthesizing information and ‘telling the story’ of vegetation transformation since settlement
• reporting ‘telling the story’ progress toward vegetation condition targets • Understanding resilience of natural ecosystems
http://portal.tern.org.au/transformation-of-australias-vegetated-landscapes-cumberland-state-forest-recommissioned-regrowth-forest-nsw
http://aceas-data.science.uq.edu.au/portal/
Where to from here?
• Scaling-up to landscape levels• More sites • Transfer and adoption
Scaling up to landscape levels Static layers
•first contact by European explorers•slope & relief derived from 30m DEM•aspect classes derived from 30m DEM•weathering layer•digital atlas of soils+•pre-European vegetation types (NVIS)
Time series response variables•rainfall anomaly (post 1900)•state-wide & national land tenure•FPC (post 1980s)*•ground cover (post 1980s)*•NDVI / EVI (post 1980s)*•native veg (tree) layers*•state-wide & national land use
• sheep DSE• cattle DSE• cropping• urban areas• Plantations• nature conservation reserves• indigenous protected areas
•Infrastructure• railways• roads
•fire regime (fire area & No. fire starts)*•otherTERN AusCover*
TERN Soils+
Landform Pattern and Topographic Position Index. 30 m – DEM SRTM
Nass Valley - ACT
Further information
• VAST-2 Handbook and brochure http://www.vasttransformations.com/